In Philly and across U.S., spring is way out of sync

Last year, Bill Heritage of Heritage Vineyards in Mullica Hill lost his entire crop of plums for wine when the trees bloomed, only to be followed by a sharp temperature plunge.

This year, he’s facing a similar trial, as trees have started blooming early and the season's roller-coastering temperatures are expected to fall into the 20s this weekend with a possibility of snow.

Nationally, a freakishly warm February broke more than 11,700 local daily records, federal officials announced Wednesday. It was Philadelphia's warmest February ever recorded, with an average temperature of 44.2 — that's 2 degrees toastier than February 1925, the previous No. 1.  And for the first time since record-keeping started in 1874, it was the first February with four days of temperatures over 70 degrees.

The National Oceanic and Atmospheric Administration said the U.S. average temperature last month was 41.2 degrees, or 7.3 degrees over normal. Scientists believe man-made global warming contributed to the rise. Yet 1954 remains the year with the warmest February the nation has recorded, illustrating that weather has always been unpredictable. 

Heritage, 54, remains optimistic,  as the plum blooms appear to still bear a protective green coating and pistils have not yet emerged. When he can produce it, his plum wine always sells out.

“So we should be OK,” he said, walking Tuesday from his fields back to his  pickup truck. He's also feeling good about his other crops, including peaches, weathering the chill. Snow can even have an insulating effect, he explained.

Snow notwithstanding, the U.S. Geological Survey confirms that spring has sprung early in Philadelphia, leading to an early allergy season, and angst for home gardeners and pros like Heritage.

Jake Weltzin, a USGS ecologist, said Philadelphia entered spring on Feb. 25, according to an index the agency devised, based on the first appearance of new leaves on  lilac and honeysuckle plants. The long-term average is March 25 (astronomical spring, the vernal equinox, is March 20).

This year, spring came “about 22 days early, compared to the long-term average,” Weltzin said.  “Some will remember the spring of 2012 – that was an early spring, too. But some portions of your region might be as much as three weeks earlier than even 2012. That’s stunning.”

Camera icon USGS
U.S. Geological Survey map shows Philadelphia entered spring Feb. 25, weeks ahead of time. Map is based on an index of first leaves.

Weltzin, who is executive director of the USA National Phenology Network, and other scientists are monitoring the frequencies of early springs. Phenology is the study of weather and climate on the timing of seasons and related biological events, such as plant blooms and bird migrations.

Humans might like to bask in an early spring, but it’s often not good for much of the natural world, including animals arriving to feed in certain locations before their prey is available.

“That’s what we’re worried about,” Weltzin said.  “We’re worried that, when the birds arrive, will there be the habitat they need?”

His network has monitored the start of spring nationally since 1900 by digging into historical records. The network has seen the biggest change since 1984.  The earliest spring recorded so far for the United States as a whole was in 2012.

Hemant Gohil, agricultural agent for Gloucester County and assistant professor at Rutgers University, said peach and apple trees are blooming about two weeks early. That can present farmers with a challenge.

“It advances the growth stage,” Gohil said. “We are two weeks ahead of the normal, historical, bloom for peaches and apples.  So it puts crops in a danger of cold damage.

“Let’s say we have a cold snap at the end of March,” Gohil explained. “In a normal year we would not worry much, because the plants would still be in the bud development stage. But this year, we are seeing them already in the bloom stage.”

Gohil said earlier blooms also result in insects arriving earlier and farmers needing to be prepared to apply treatments earlier.  

Farmers have always dealt with the vagaries of nature, says Heritage, who grew up on the farm, which his family has owned stretching back to 1853.  Some of the farm was sold off.  Now, Heritage has about 150 acres of wine grapes, peaches, apples, and plums. The vineyard has become key, and Heritage has a wine tasting room on Route 322 that he is improving.

He’s diversified enough that a partial loss of a crop is not devastating, unlike in years past when many farmers focused on a single crop.  He says he’s seen so many weather challenges over the years that he’s not sure that he can attribute any anomaly to climate change. 

“Mother Nature holds the reins,” Heritage said. “We just have to be a little more flexible these days.”

Staff writer Anthony R. Wood contributed to this article.